The perception of presence has been variously referred to as co-presence (Goffman, 1959;
Biocca et al., 2001, 2003), social presence (Short et al., 1984; Gunawardena, 1995) and
co-location (Biocca et al., 2003). Despite the many multiple labels, they all refer to the idea of
the perception of others as being in the same space. We refer to this idea as social perception.